Question: What is the greatest common factor of $4$ and $8$ ? Another way to say this is: $\operatorname{gcf}(4, 8) = {?}$
The greatest common factor is the largest number that is a factor of both $4$ and $8$ The factors of $4$ are $1$ $2$ , and $4$ The factors of $8$ are $1$ $2$ $4$ , and $8$ Thus, the greatest common factor of $4$ and $8$ is $4$. $\operatorname{gcf}(4, 8) = 4$